C0C0 C0IR Run off PPM reading keeps shooting up even after a heavy flush. HELP! (in flower)

Medium - COCO/PERLITE 70/30
Autoflower - DC Collectibles oz
Week - 6 stretch just started

Hey guys hope everyone is doing well considering the ongoing pandemic/lockdowns. Im having some high run off ppm issues and unfortunately even HEAVY flushing hasn't solved it. By heavy flushing I do mean HEAVY flushing where I literally held the pot over a bucket to catch run off and used a shower head to leach the coco. After flushing run off PPM was 300ppm which was down from well over 4500ppm. Fast forward to today after the coco dried a bit I watered with 350ppms and the run off was over 3500ppm. WTF am I doing wrong?? Im worried this will ruin the stretch and the final yield.

Any advice is appreciated

Also incase my tds meter is being goofy just ordered another from a well respected Australian manufacturer. I really hope to fix this soon or this run will be ruined.

Never let your coco dry
Drying coco also increases the ppm as your nutes dry out leaving behind the salt.
The longer you leave your coco to dry, the more run off the next feeding should be
Try get used to EC instead. Being in Australia one can't be too sure if people are using the x500 or x700 conversion.

goofy81 said:

Never let our coco dry
Drying coco also increases the ppm as your nutes dry out leaving behind the salt.
The longer you leave your coco to dry, the more run off the next feeding should be
Try get used to EC instead. Being in Australia one can't be too sure of people are using the x500 or x700 conversion.

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How do you prevent overwatering if you dont let it dry? genuine question because I've been getting some mixed info on YouTube. "welcome to the grow tent" suggests to wait till the pot feels light to the hand which is what I was doing. Is that bad? Damn YouTube is like wikipedia for high school exams it seems like lol.

Yes, if you're in the steering stage to grow roots, you can dry it out a bit. But not to the extent you're thinking. Look up dryback.

In a professional greenhouse with much at stake. One would measure the runoff after the first feed Everyday.
Then depending on the program, the dripper might turn on every 30 minutes for like 20+small feeds throughout the day.

Edit. Was having dinner hence my brief reply

But there is no such thing as overwatering in coco.
If i give my coco pot (7gl) 20 litres of water and 50litres of water. After 5 minutes the pot would weigh the same.
There is a thing about people saying overwatering when the roots haven't filled the coco. But that's more about wasting nutrients and starting in a pot too big rather than over watering.
A trick to decide on watering is to weigh your coco pot when it's dry, and when it's full. If your 5gallon coco pot can hold 5 litres of water and you're feeding every time the coco pot is 2.5kg less, you're drying it back 50%.
Some people may do a dryback of 30%, so whatever works for you. Or just go by instinct and lift with your hands.
typing on my phone so this info might be a bit messy

goofy81 said:

Yes, if you're in the steering stage to grow roots, you can dry it out a bit. But not to the extent you're thinking. Look up dryback.

In a professional greenhouse with ai much at stake. One would measure the runoff after the first feed Everyday.

Click to expand...

Wow thank you for letting me know. I will increasing waterings between feedings. Good thing I posted here otherwise I would have never known.

Of possible interest...

Ok haven't read that link but I would add.

The biggest decider of your watering schedule for coco is pot size vs plant size
Imagine a 1lb plant in 12 gallons.
Eg. You need to Water 3 times a day to prevent dryback of more than 20%
1lb plant in 7 gallons, water 5 times a day
1lb plant in 3 gallons, water 12 times a day

Also varies with your root mass and climate too.

Ok I've made a graphic that should help everyone out and show how much these plants transpire.
I'm lucky enough to have a weight sensor on one of my pots.
Having data in any setup prevents guessing.
Also shows how you can't over water in coco.

goofy81 said:

Ok I've made a graphic that should help everyone out and show how much these plants transpire.
I'm lucky enough to have a weight sensor on one of my pots.
Having data in any setup prevents guessing.
Also shows how you can't over water in coco.

View attachment 4941077

Click to expand...

Holy shit you are a god! I hope someone will sticky this graph and credit you in the newbie section. This is prime info for newbies!!

SupremeBudDrongo said:

Medium - COCO/PERLITE 70/30
Autoflower - DC Collectibles oz
Week - 6 stretch just started

Hey guys hope everyone is doing well considering the ongoing pandemic/lockdowns. Im having some high run off ppm issues and unfortunately even HEAVY flushing hasn't solved it. By heavy flushing I do mean HEAVY flushing where I literally held the pot over a bucket to catch run off and used a shower head to leach the coco. After flushing run off PPM was 300ppm which was down from well over 4500ppm. Fast forward to today after the coco dried a bit I watered with 350ppms and the run off was over 3500ppm. WTF am I doing wrong?? Im worried this will ruin the stretch and the final yield.

Any advice is appreciated

Click to expand...

Don't let coco dry at all. Dry coco causes salt buildup.

Are your plants showing issues?

You flatter too much!
Just trying to help people 'understand' why they do what they do.
Having data can show so many things!
I mean just from that you can even see plants transpire at night even in my case 750gr of weight was lost which is like 750ml overnight.
The bottom graph is stretched in, but the bottom graph was on a 13 gallon pot. You can see it takes SO long for the coco to dryback which is why using 13gallons, i watered only 3 times a day.

Having a smaller pot in coco is advantageous in this way.
With a smaller pot filled with roots, the plant is taking all you're giving them that day,
With a massive pot with not much roots, half the nutrients have been in there for days!

twentyeight.threefive said:

Don't let coco dry at all. Dry coco causes salt buildup.

Are your plants showing issues?

Click to expand...

They weren't for the past 5-6 weeks but this week I started to notice the very bottom leaves especially the first 2 3 blade leaves started to get crumbly. Immediately I leached the medium and checked the run off. Thats when I found the 4500+ppm issue.

Dry coco is also especially bad AND can give false EC runoff readings if you measure.
HOW?
When coco is dry and you water it, it'll create channels, so half your feed goes straight down without having a chance for the coco to absorb the nutrients.

I always try to check my runoff ec at the VERY end.
Sometimes if you check during feed, it'll be extremely low, then if your runnoff is still coming out 15 minutes later, it might be extremely high.

There's just too much infomation to know with coco ! I run pure coco, but you probably understand how mixing it with chunkier substances (for better drainage) can benefit a LARGE pot of coco,

SupremeBudDrongo said:

They weren't for the past 5-6 weeks but this week I started to notice the very bottom leaves especially the first 2 3 blade leaves started to get crumbly. Immediately I leached the medium and checked the run off. Thats when I found the 4500+ppm issue.

Click to expand...

If you feed at a lower EC then you can get away with letting the coco dry out a little, but I don't recommend it. It defeats the purpose of using coco.

As stated above, once the root system has filled the pot it's impossible to overwater coco.

You also said, "I will increasing waterings between feedings." I hope you meant with nutrients. Coco is always fed nutrients, never plain water. GL

twentyeight.threefive said:

If you feed at a lower EC then you can get away with letting the coco dry out a little, but I don't recommend it. It defeats the purpose of using coco.

As stated above, once the root system has filled the pot it's impossible to overwater coco.

You also said, "I will increasing waterings between feedings." I hope you meant with nutrients. Coco is always fed nutrients, never plain water. GL

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yep mr Goofy81 gave me a stellar run down. Will aim to water 6x a day minimum from here on out. I wish I posted this question in this forum earlier!

I know this is a little off topic. I see a lot of people grow with coco. It looks so difficult so can I ask why. I could see why if your up for challenges. So I’m only curious on what the advantage is growing in such a complicated method. Or do I read into it on it being more complicated than it really is.

Autodoctor said:

I know this is a little off topic. I see a lot of people grow with coco. It looks so difficult so can I ask why. I could see why if your up for challenges. So I’m only curious on what the advantage is growing in such a complicated method. Or do I read into it on it being more complicated than it really is.

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Coco is not complicated at all.
Start in small containers.
Feed every day with a weak nute solution to substantial run off using a pH around 6.0........once a day in veg and at least twice a day in flower.
Never let it dry out.
Never give plain water.
Daily feeding to run off replenishes the nutes, pulls in fresh oxygen to the roots, and prevents salt build up.

MickFoster said:

Coco is not complicated at all.
Start in small containers.
Feed every day with a weak nute solution to substantial run off using a pH around 6.0........once a day in veg and at least twice a day in flower.
Never let it dry out.
Never give plain water.
Daily feeding to run off replenishes the nutes, pulls in fresh oxygen to the roots, and prevents salt build up.

Click to expand...

Everyone’s probably getting sick of this pic in the last week but this is using 0.9EC base A/B and a little calmag when needed TWICE daily feeding.

@Autodoctor

using an automated DIY drip system (which will be changed up for next run to a single loop with branches off)

My nutrient manufacturer would have me using 2.4EC at this stage in their feeding chart!

What do the plants look like? Or did you just decide to check the runoff, thought it was too high, and then started flushing?

Was there a problem with the plants?